波动在弹性介质中，单位时间所传播的距离称为（）。
A.声速
B.声程
C.频率
D.声强
参考答案：A
The people upstairs __________ when I __________ to sleep last night.[ ]
A. danced; was going
B. were dancing; got
C. had danced; went
D. are dancing; get
肛门灼热疼痛，肛窦焮红， * * 红肿，伴心烦口苦，尿黄，大便干燥，舌红苔黄腻，脉滑数，方选（）
A.凉血地黄汤
B.玉女煎
C.止痛如神汤
D.龙胆泻肝汤
E.萆薢渗湿汤
ople upstairs __________ when I __________ to sleep last night.[ ]